Add prefix, suffix, dir args to TemporaryDirectory

[q0w]

Closes #112
I also used black (maybe I should not?) because there is no rule about the code style

[Tinche]

Looks good. Could you add a line to the changelog in the readme?

[codecov-commenter]

Codecov Report

Merging #116 (5ae63a4) into master (8895eb4) will increase coverage by 0.03%.
The diff coverage is 80.00%.

@@            Coverage Diff             @@
##           master     #116      +/-   ##
==========================================
+ Coverage   89.56%   89.59%   +0.03%     
==========================================
  Files          10       10              
  Lines         297      298       +1     
==========================================
+ Hits          266      267       +1     
  Misses         31       31              

Impacted Files	Coverage Δ
src/aiofiles/base.py	70.96% <0.00%> (ø)
src/aiofiles/tempfile/__init__.py	95.08% <100.00%> (+0.08%)	⬆️

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[q0w]

Done

[Tinche]

Thanks a lot!